Keyless watch



March 6, 1928. 1,661,232

G. PERRET KEYLESS WATCH Filed Oct. '19, 1926 [770621 for Geo g'esPer/"6f b flea gwvw Patented Mar. 6, 1928.

UNITED STATES PATENT oFFics.

GEORGES FERRET, OF LA CHAUX-DE-FONDS, SWITZERLAND, ASSIGNOR TO HANSWILSDORF, OF BIENNE, SWITZERLAND.

KEYLESS WATCH.

Application filed October 19, 1926, Serial No. 142,725, and inSwitzerland October 30, 1925.

The subject of the present invention is a keyless watch having a winderconnected to the winding stem in such manner that on operating thewinder'the winding stem is rotated and the main spring wound.

In watches of this kind, and particularly in small watches where thewinder is, as it were, connected to the watch case, the joints betweenthe case on the one hand and the O winder and the winding stem on theother hand become in course of time, passages easily penetrable by dust,moisture and other matters liable to damage the movement or to interferewith the operation of the watch.

It has already been attempted to obviate this disadvantage by differentmeans, such as covers, packing and the like, but none of such means hasgiven satisfaction, some being too complicated and expensive and othershardly practical, of short life or inadequate fully to satisfy therequirements.

The problem of effecting tightness of the joints between the winder, thewinding stem and the watch case has been solved satisfactorily in thewatch forming the subject of the present invention.

The watch of the invention is characterized in that the winder and thewinding stem are connected with one another in such manner that thelatter always follows the movement of the rotation imparted to thewinder and that the winder is adapted to perform an axial movementrelatively to the winding stem, the winder including a thread ed portionwhereby it may be assembled to form a rigid unit with the watch case,the latter being associated with a corresponding threaded part.

Figs. 1 and 2 of the accompanying drawing illustrate in section thecharacteristic parts of one embodiment of the invention. The winder isshown in two different positions in the two figures.

The rim 1 of the watch case is formed with a screw-threaded opening 2into which is screwed a cylindrical plug 3 projecting beyond theperiphery of the rim. The projecting part of this plug has an externalleft handed screw-thread. The winding stem 4 passes freely through anaxial passage 5 of the plug 3 and carries at its upper end a head 6screwed on to said stem. The head 6 is fitted in a cylindrical recess 7of the body 8 of the winder. The latter is fitted with two screws 9, 10,each of which engages at its inner end in a longitudinal groove 11 or 12of the head 6. In the space formed on the one hand by the recess 7 inthe body of the winder and on the other hand by a counter-bore 13 in thehead (3, is housed a helical spring 1e continuously urg mg the winderupwards relatively to the winding stem.

The body 8 of the winder is formed at the entrance to the recess 7 withan internal screw-thread 15 corresponding to the external screw-threadof the projecting part of the plug 3, which permits of screwing the body8 of the winder on to the plug 3 as shown in Fig. 1 of the drawing. Onthe plug 3 is fitted a packing member 16 formed by a washer of elasticmaterial impermeable to water. Thus, when the body of the winder isscrewed home on the plug 3 (Fig. 1), the joint between the case and thewinder is quite tight, preventing passage of moisture and dust.

To wind the watch and set the hands, the body 8 of the winder isunscrewed by rotating it in the direction for winding. In this operationthe screws 9 and 10 entrain the winding stem 4, while moving axially inrelation to the latter in the respective grooves 11 and 12. As soon asthe body 8 of the winder is separated from the plug 3, the spring 14thrusts it into the position indicated in Fig. 2, in which the screws 9and 10 abut against the upper ends of the grooves 11 and 12. finding canthen be effected and the hands set.

If the setting mechanism is of the pull type, or of a type known asnegative it is sufficient to pull the winder in order to bring thewinding stem and the mechanism which it operates to setting position.

After the hands are set the winder is re turned to position by screwingit on to the plug 3, as the result of which the spring 1% is compressedanew while the screws 9, 1O abut against the lower ends of the grooves11 and 12 and force the winding stem to winding position.

Modifications of the subject of the invention differing from the exampleshown are contemplated within the scope of the claims. Thus, the plug 3can be forcibly driven into the opening 2 in the rim or may be solderedto the latter. Also the head 6 may be otherwise fixed on the windingstem. Also the construction may include a winding stem and a head in onepiece. The Washer 16 is not essential because the joint is perfectlytight Without the need for employment ot' packing, In certain variantsthe pendant of the case may replace the plug 8. The upper part of thependant would then include a threaded portion to connect With the bodyneeraaa provided with anexternal head of larger diameter than said stem,a Winder screwing upon a fixed part of the Watch casing and beingrecessed to receive said head, a pin and slot connection between saidhead and Winder compelling them to rotate together While at the sametime permitting independ ent reciprocatory movement of said memhers, theend Walls of said slot cooperating with said pin to cause said stem andWinder to reciprocate together at the ends of their range of independentreciprocatory move ment, one of said members being formed endwise With arecess, and a spring held in compression Within said recess between saidmemioers.

In testimony whereof l have signed my name to this specification.

PERRFI".

GEORGES

